I'm back, here's the deal. After conferring with Greg, and digesting all of the good info from Eric, Rainman, & Bobad, I'm having 4 tons of powdered ag lime delivered and spread Monday - the total cost is $45/ton ($180). I'm also going to do a little fertilizing and hopefully get the pond back in shape.
Thanks very much for all of your help. I'll update and add pictures at a later date.
Randy

Just do it...